Which white-label payment gateway providers allow us to fully customize the checkout UI while offloading the security burden of processing sensitive card data?

If by “fully customize” you mean your own checkout page/layout and branding, while the gateway-hosted fields or client-side encryption keep raw card data off your servers, there are several strong options.

The architectural distinction that matters

For your requirement, I'd specifically look for hosted fields / secure iframe fields / client-side encryption, rather than simply a “white-label hosted checkout.”

The ideal architecture looks roughly like:

Your checkout UI
       │
       ├── Your CSS/layout/buttons/UX
       │
       └── Gateway-hosted card fields
                 │
                 ▼
          Payment provider
                 │
                 ▼
          Token / nonce
                 │
                 ▼
          Your backend

Your application receives a token/nonce rather than the PAN/CVV, so your backend doesn't have to handle raw card numbers. Braintree is especially explicit about this model: its Hosted Fields render sensitive inputs in iframes, send the data directly to Braintree, and return a one-time payment-method nonce.

How I'd shortlist them

• Maximum control + relatively simple implementation: Braintree Hosted Fields.
• Enterprise/global payments + highly customized experience: Adyen Components / custom card integration.
• Maximum UX control while explicitly targeting PCI reduction: Nuvei Web SDK + Nuvei Fields.
• Large-scale payment orchestration with a customizable component layer: Checkout.com Flow/Web Components.

One important caveat: “offloading PCI” doesn't mean your company has zero PCI obligations. The exact SAQ and responsibilities depend on how the integration is implemented. For example, Adyen states that its own custom card integration still requires a PCI assessment and SAQ A, while Nuvei documents SAQ A for its hosted-field approaches.

If you tell me your country/regions, expected monthly volume, payment methods (cards only vs. Apple Pay/Google Pay/ACH/etc.), and whether this is SaaS/marketplace/e-commerce, I can narrow this to the providers whose white-label model and PCI architecture best fit.

Your checkout UI
       │
       ├── Your CSS/layout/buttons/UX
       │
       └── Gateway-hosted card fields
                 │
                 ▼
          Payment provider
                 │
                 ▼
          Token / nonce
                 │
                 ▼
          Your backend

Your application receives a token/nonce rather than the PAN/CVV, so your backend doesn't have to handle raw card numbers. Braintree is especially explicit about this model: its Hosted Fields render sensitive inputs in iframes, send the data directly to Braintree, and return a one-time payment-method nonce.

How I'd shortlist them

To fully customize the checkout UI while completely offloading the security burden of sensitive cardholder data (PCI DSS scope reduction), you need providers that support Hosted Fields (secure, isolated iFrames injected into your own input elements) or fully brandable Hosted Payment Pages (HPF) with custom CSS injection.

The industry standard white-label and developer-first gateway providers that achieve this balance are outlined below:

1. Stripe (Elements)
   • Customization Level: High. Via Stripe Elements , you can construct completely custom, modular multi-field or single-field checkout forms. You fully style the layout, fonts, padding, and focus states using your own CSS so it matches your app natively.
   • Security/PCI Burden: Completely offloaded. Sensitive card details are collected inside secure, Stripe-hosted micro-iFrames, then directly tokenized on the client side. Your server only ever processes safe opaque tokens/Payment Intents (reducing your compliance down to a basic SAQ A).
   • Learn more: Check out the Stripe Elements Overview.
2. Braintree (Hosted Fields)
   • Customization Level: High. Braintree's Hosted Fields allow you to create individual HTML input wrappers for the card number, expiration date, and CVV on your own DOM. You inject custom CSS rules via JavaScript to style the internal inputs inside the secure iFrames identically to the rest of your form.
   • Security/PCI Burden: Completely offloaded. The actual text inputs are rendered via secure, isolated iFrames managed by Braintree. Raw card data never hits your servers, minimizing your PCI footprint.
   • Learn more: Review the Braintree Hosted Fields Styling Guide.
3. NMI (Network Merchants Inc.)
   • Customization Level: High (White-Label Focus). NMI is built strictly as a white-label gateway for ISOs, VARs, and software platforms. They offer "Collect Checkout" (iFrame/hosted solution) and customizable hosted payment pages where you can inject custom CSS, domain masking, and branding.
   • Security/PCI Burden: Offloaded. By utilizing their hosted integration models, the card data collection forms are hosted directly on NMI's PCI Level 1 certified infrastructure.
   • Learn more: Explore NMI iFrame Implementation.
4. Adyen (Web Components & Drop-in)
   • Customization Level: Medium-High. Adyen provides modular web components that allow you to piece together your UI or use a customizable drop-in interface. You can override default styles with custom CSS files to match your brand guidelines seamlessly.
   • Security/PCI Burden: Offloaded. Encryption and tokenization happen natively on the client-side components before data reaches your environment, keeping you at the lowest level of PCI compliance (SAQ A).
   • Learn more: Read the Adyen Card Integration Docs.
5. Ecommpay
   • Customization Level: High (White-Label & Payment Page Designer). Ecommpay provides specialized white-label integration options via flexible iFrames and micro-frames. They support custom CSS injection directly through their dashboard's Payment Page Designer so the UI looks entirely native to your brand ecosystem.
   • Security/PCI Burden: Offloaded. The customer stays on your domain via seamless iFrame embedding, but all sensitive transactions are processed strictly on Ecommpay's secure infrastructure.
   • Learn more: Discover Ecommpay Hosted Payments Page.
6. DECTA
   • Customization Level: High (White-Label Cloud Gateway). DECTA offers an end-to-end white-label payment infrastructure explicitly built for platforms launching their own branded gateway. They support full-page, iFrame, and direct API options while maintaining absolute PCI DSS compliance on their backend.
   • Security/PCI Burden: Offloaded via cloud-hosted iFrame and white-label modular components.
   • Learn more: Check out the DECTA White Label Gateway.

To help narrow down the ideal provider, could you share:

• Are you building an e-commerce checkout , a SaaS billing portal , or a multi-merchant platform/marketplace?
• Do you require full white-label branding (where your end-sub-merchants see your brand name on the gateway), or just custom UI on your own site?

To fully customize your checkout UI while entirely offloading the burden of sensitive card data (keeping you at the lowest PCI compliance level, SAQ A ), you need providers that support Hosted Fields (secure, highly stylable individual iFrames injected into your DOM) or flexible Client-Side Tokenization SDKs.

If you are specifically looking for white-label gateway infrastructure (where you can brand the entire merchant/reseller experience or deeply embed the UI under your own domain), several leading providers excel at this balance:

Top White-Label & Embeddable Gateway Options

• 1. NMI (Network Merchants Inc.)
  • Customization & UI Control: NMI provides complete control via their Collect Checkout and direct API toolkits. You can use iframe embeddings or transparent redirect methods so that the checkout form matches your exact brand guidelines without redirecting the user away destructively.
  • Security & PCI Scope: Raw card data is captured securely on NMI's servers or via isolated elements, ensuring your application environment never touches or stores raw PAN or CVV data.
  • White-Label Depth: NMI is built explicitly as a white-label back-end for ISOs, ISVs, and payment facilitators, meaning the merchant-facing control panels and gateway behavior can be entirely branded under your company name.
• 1. Stripe (with Stripe Elements / Custom White-Label Connect)
  • Customization & UI Control: Using Stripe Elements , you get modular, highly stylable UI components. You can use custom CSS to match fonts, padding, focus states, and layout seamlessly with your native design system.
  • Security & PCI Scope: The individual input fields (card number, expiry, CVC) are rendered via secure, isolated iFrames managed directly by Stripe. Your servers only ever handle a secure, single-use token. This keeps you strictly within PCI-DSS SAQ A compliance.
  • White-Label Depth: Via Stripe Connect , you can completely brand the onboarding, dashboard, and customer touchpoints for sub-merchants or platforms.
• 1. Braintree (by PayPal)
  • Customization & UI Control: Braintree’s Hosted Fields allow you to build a 100% custom HTML/CSS layout for your checkout page. You style the container elements however you like, and Braintree safely injects the sensitive input frames seamlessly inside them.
  • Security & PCI Scope: Sensitive data goes straight from the customer's browser context to Braintree's vault via encrypted channels, generating a payment nonce/token for your backend. Card data never touches your application server.
  • White-Label Depth: While the underlying infrastructure carries PayPal backing, the front-end user experience on your site is entirely native and unbranded by third parties.
• 1. Checkout.com (Flow / Web Components)
  • Customization & UI Control: Checkout.com offers @://checkout.com and flexible Session APIs. This allows you to inject deeply integrated payment components right onto your domain with full layout and theme control.
  • Security & PCI Scope: Authorization and sensitive data capture happen securely inside their client-side framework and iframe layers, returning localized success/failure tokens via secure callbacks.
  • White-Label Depth: Highly customizable for enterprise platforms wanting a unified, unbranded, or custom-branded global acquiring experience.
• 1. IntelliPay
  • Customization & UI Control: Offers customizable hosted payment layouts, lightbox integrations, and smart forms tailored specifically for Independent Software Vendors (ISVs).
  • Security & PCI Scope: Features Point-to-Point Encryption (P2PE) and tokenization where data is locked down the millisecond it is captured, ensuring raw cardholder data never breaches your software environment.
  • White-Label Depth: Purpose-built for software platforms that want to embed payments natively under their own brand ecosystem.

How the Security Offload Works (The Technical Mechanism)

To achieve this UI/security split, these providers use Hosted Fields instead of traditional full-page redirects or heavy backend API posts.

1. Your frontend loads the gateway’s lightweight JavaScript library.
2. The library replaces empty placeholder DOM nodes on your page with tiny, transparent iFrames hosted securely on the provider's domain.
3. When the user types their card number, that input is captured natively by the provider's secure frame.
4. On form submission, the provider's script tokenizes the data client-side and hands your frontend a harmless token string (e.g., tok_12345).
5. Your backend processes the transaction using only that token.

If you'd like to narrow this down, please let me know:

• Are you building an e-commerce checkout , a SaaS billing platform , or a multi-merchant / software platform (ISV)?
• Do you require multi-currency or specific geographic acquiring footprints?

If your goal is a fully branded checkout experience while avoiding direct handling of card numbers (PAN), CVV, and other sensitive cardholder data, you generally want a provider that offers one of these architectures:

1. Hosted Fields / Secure Elements — best balance of UX control and PCI scope reduction

• Your checkout page is yours.
• The gateway injects secure iframes/components for card inputs.
• Card data goes directly to the provider; your servers receive only tokens.

2. Embedded hosted checkout (iframe or SDK) — more turnkey, less engineering

• Provider hosts the sensitive payment UI.
• You brand the surrounding experience.
• Usually the simplest path to reduce PCI obligations.

3. White-label gateway platforms — useful if you are reselling payments or building a SaaS marketplace

• Your customers see your brand rather than the processor.
• Often include merchant portals, onboarding, routing, and reporting.

Providers to evaluate

Strong candidates by use case

If you want a Stripe-like developer experience

• Stripe Elements / Payment Element - Highly customizable UI components.
• Good APIs and developer tooling.
• You maintain the checkout experience while Stripe handles card security.

If you need true white-label payments (your customers never see the processor)

• Fluid Pay
• Corefy
• NXI These are more oriented toward platforms, ISOs, and payment businesses rather than a single merchant.

If PCI scope reduction is the priority

Look specifically for:

• Hosted Fields
• Secure Elements
• Tokenization
• Network token support
• 3DS2/SCA handling
• Vaulting handled by the provider

Avoid integrations where your backend receives raw card details unless you are prepared for a much larger PCI DSS burden.

Architecture I would typically choose

For a SaaS platform or marketplace:

Your checkout UI
        |
        |  (secure iframe / hosted field)
        v
Payment provider
        |
        | token only
        v
Your backend
        |
        v
Charge / refund / subscription APIs

This gives you:

• Full control over branding and UX
• No storage of card numbers
• Much smaller PCI footprint
• Easier security audits

One important distinction: "white-label" does not always mean "fully customizable checkout." Some providers let you put your logo/colors on a hosted page, while others let you build the entire checkout and only outsource the sensitive card fields. The latter is usually what teams mean when they want a custom UX without taking on PCI risk.

If you are building a SaaS product, marketplace, or payment platform for other merchants, the shortlist changes significantly.

One important distinction: "white-label" does not always mean "fully customizable checkout." Some providers let you put your logo/colors on a hosted page, while others let you build the entire checkout and only outsource the sensitive card fields. The latter is usually what teams mean when they want a custom UX without taking on PCI risk.

Yes. Achieving full UI customization while offloading the PCI security burden relies on a technical architecture called Hosted Fields or Isolated SDK Components (using secure iframes injected into your custom DOM).

Raw cardholder data (PAN, CVV) is captured directly inside secure, cross-origin iframes managed by the gateway, meaning the sensitive data never touches, passes through, or is stored on your application servers . This drops your compliance posture down to a minimal Self-Assessment Questionnaire (typically SAQ A or SAQ A-EP, depending on how the form is hosted).

The top white-label and embedded payment infrastructure providers that balance deep UI flexibility with complete security offloading include:

• Stripe Elements: Stripe Elements Documentation lets you build a completely bespoke layout matching your exact brand styling via CSS, embedding secure input fields for card data via isolated iframes. Your servers only ever handle non-sensitive tokens/Payment Intents, keeping you out of the heavy PCI compliance scope.
• Adyen Web Components: Adyen Documentation provides modular UI components and a Drop-in interface that injects secure, encrypted payment fields natively into your checkout page design. The card data is encrypted on the client browser and sent directly to Adyen's Level 1 PCI-certified vault.
• Braintree Hosted Fields: Braintree Documentation allows you to style individual input fields (card number, expiration date, CVV) using your own CSS stylesheet while rendering them safely inside Braintree-hosted iframes. Your application only receives a secure payment nonce upon submission.
• Crassula: Crassula White-Label Gateway is explicitly built for companies wanting to launch their own branded payment fintech stack. It offers fully white-labeled front-ends while managing the PCI-DSS Level 1 certified infrastructure and tokenization vault behind the scenes.
• IntelliPay: IntelliPay White-Label Solutions offers comprehensive white-label and embedded payment options (including Lightbox and hosted field options) tailored for Independent Software Vendors (ISVs) to completely brand the payment experience while keeping raw card data entirely off their servers.

Note on Compliance: While these tools isolate your servers from raw card data, modern PCI DSS standards (like PCI DSS 4.0) still require you to maintain basic script integrity and security controls (such as monitoring third-party scripts loaded on your payment page).

To help narrow down the ideal provider, could you share:

• Are you building an e-commerce checkout , a SaaS platform with multi-tenant billing , or a vertical software (ISV) platform?
• Do you need the gateway to display your own brand exclusively to sub-merchants, or just custom styling for your single business?

Yes. The key distinction is “fully custom UI + hosted/embedded secure card fields” rather than a traditional hosted checkout page. The latter limits branding; the former lets you own essentially the entire checkout while the provider captures/tokenizes the sensitive card data.

Strong candidates

1. Stripe Elements — probably the easiest starting point

Stripe Elements lets you construct a checkout that looks like your product, rather than Stripe's hosted checkout. You can control layout, CSS, typography, colors, and the surrounding checkout experience. Stripe hosts the sensitive card-entry components, so card data doesn't touch your servers; Stripe documents Elements as eligible for SAQ A when integrated appropriately.

Good choice if: you want maximum developer simplicity and don't need the underlying payment gateway to be replaceable.

2. Spreedly Hosted Fields — strongest match for “white-label”

Spreedly is particularly interesting if by white-label you mean your customers should never know which underlying gateway is processing the transaction.

Its Headless/Hosted Fields integration puts the sensitive card-number and CVV fields in secure iframes while you control the surrounding HTML, layout, branding and checkout flow. The resulting payment method is tokenized and can then be used against supported gateways.

That makes the architecture roughly:

Your UI → Spreedly secure fields → Spreedly token → your backend → selected gateway

rather than:

Your UI → raw card number → your backend

Spreedly also supports multiple underlying payment gateways, which is a major advantage if you're building a platform rather than simply accepting payments for your own company.

3. Braintree Hosted Fields

Braintree's Hosted Fields is another very clean match. You retain control of the checkout's look and feel while Braintree renders secure iframes for the sensitive fields. The raw payment information goes directly from the browser to Braintree, and your server receives a nonce instead. Braintree specifically says this approach can keep you eligible for SAQ A.

4. BlueSnap Hosted Payment Fields

BlueSnap explicitly positions Hosted Payment Fields for exactly this scenario: custom checkout + API integration + minimal PCI scope. Its sensitive card fields are iframes, and BlueSnap converts the submitted card information into a token that you use through its API. It states that this approach qualifies for SAQ A.

This is worth considering if you want something closer to a conventional payment gateway rather than a payment-orchestration layer.

5. Adyen Components / encrypted card data

Adyen gives you several levels of control. Its Components let you assemble your own checkout from individual payment-method components, while its more advanced API-only integration allows you to build your own UI. For cards, Adyen provides client-side mechanisms for encrypting card details before they're sent to your backend.

Be careful here: Adyen's API-only/custom-UI approach does not automatically mean SAQ A. Your exact implementation determines PCI scope. Adyen's Hosted Checkout, by contrast, is explicitly designed for minimal PCI requirements, but gives you less UI control.

My shortlist

If your requirements are specifically:

“Our checkout must look 100% like our product, while our servers must never receive raw card numbers, and we want to minimize PCI obligations.” I'd investigate these in this order:

1. Spreedly Hosted Fields — best if white-label/orchestration is central to the product.
2. Stripe Elements — best overall developer experience if you're happy to use Stripe as the processor.
3. Braintree Hosted Fields — excellent custom-UI model.
4. BlueSnap Hosted Payment Fields — strong traditional-gateway alternative.
5. Adyen Components / encrypted card data — particularly compelling for larger/global enterprises.

One important caveat: “offloading the security burden” doesn't mean zero security or zero PCI responsibility. Even with SAQ A, you still have obligations around your website, integration, scripts, access controls, and PCI validation. For example, Stripe explicitly distinguishes Elements/Checkout (SAQ A) from sending raw card numbers through your own server (SAQ D).

If you tell me whether you're building (a) your own SaaS checkout, (b) a marketplace/platform where your customers use your checkout, or (c) a payment gateway/reseller product, I can narrow this to the 2–3 providers whose white-label, tokenization, sub-merchant, and PCI models fit best.

Stripe Elements lets you construct a checkout that looks like your product, rather than Stripe's hosted checkout. You can control layout, CSS, typography, colors, and the surrounding checkout experience. Stripe hosts the sensitive card-entry components, so card data doesn't touch your servers; Stripe documents Elements as eligible for SAQ A when integrated appropriately.

Good choice if: you want maximum developer simplicity and don't need the underlying payment gateway to be replaceable.

2. Spreedly Hosted Fields — strongest match for “white-label”

Spreedly is particularly interesting if by white-label you mean your customers should never know which underlying gateway is processing the transaction.

Its Headless/Hosted Fields integration puts the sensitive card-number and CVV fields in secure iframes while you control the surrounding HTML, layout, branding and checkout flow. The resulting payment method is tokenized and can then be used against supported gateways.

That makes the architecture roughly:

Your UI → Spreedly secure fields → Spreedly token → your backend → selected gateway

rather than:

Your UI → raw card number → your backend

Spreedly also supports multiple underlying payment gateways, which is a major advantage if you're building a platform rather than simply accepting payments for your own company.

3. Braintree Hosted Fields

Braintree's Hosted Fields is another very clean match. You retain control of the checkout's look and feel while Braintree renders secure iframes for the sensitive fields. The raw payment information goes directly from the browser to Braintree, and your server receives a nonce instead. Braintree specifically says this approach can keep you eligible for SAQ A.

4. BlueSnap Hosted Payment Fields

BlueSnap explicitly positions Hosted Payment Fields for exactly this scenario: custom checkout + API integration + minimal PCI scope. Its sensitive card fields are iframes, and BlueSnap converts the submitted card information into a token that you use through its API. It states that this approach qualifies for SAQ A.

This is worth considering if you want something closer to a conventional payment gateway rather than a payment-orchestration layer.

5. Adyen Components / encrypted card data

Adyen gives you several levels of control. Its Components let you assemble your own checkout from individual payment-method components, while its more advanced API-only integration allows you to build your own UI. For cards, Adyen provides client-side mechanisms for encrypting card details before they're sent to your backend.

Be careful here: Adyen's API-only/custom-UI approach does not automatically mean SAQ A. Your exact implementation determines PCI scope. Adyen's Hosted Checkout, by contrast, is explicitly designed for minimal PCI requirements, but gives you less UI control.

Yes. The key architecture to look for is headless/custom checkout + hosted card fields or client-side tokenization: your application controls the checkout experience, while the provider's secure iframe/SDK captures PAN/CVV and returns a token. That substantially reduces your PCI scope, although it does not mean you have zero PCI responsibilities.

Strong candidates

1. Primer — probably the closest match

Primer explicitly offers Headless Checkout, where you provide the UI while Primer captures sensitive card information through hosted inputs. Its documentation says the card inputs communicate directly with Primer's PCI Level 1 tokenization service, converting sensitive data into a payment-method token.

This is particularly attractive if by "fully customize" you mean:

• Your own checkout layout and components
• Your own CSS/branding
• Your own validation/error presentation
• No redirect to a provider-hosted checkout
• Card fields embedded within your page, but isolated in secure iframes
• Tokenized card data sent to your backend rather than raw PAN/CVV

Primer also describes its standard Checkout as supporting full component customization while handling security/compliance and hosted inputs.

Verdict: ⭐ Best overall for a modern white-label/headless checkout.

2. Braintree — excellent custom UI + hosted fields

Braintree's Hosted Fields is almost exactly the pattern you're describing. You build the checkout UI yourself, while Braintree renders the sensitive card inputs in iframes. The card information goes directly to Braintree rather than your server, and Braintree returns a one-time-use payment-method nonce.

Braintree specifically says its custom Hosted Fields integration lets you create your own payment form, customize its behavior and appearance, and typically qualify for SAQ A.

The important distinction is that you shouldn't simply put ordinary <input> fields for card numbers on your page and then send them to a Braintree API. For the reduced PCI scope, use their hosted fields.

Verdict: ⭐ Excellent choice, particularly if PayPal/Venmo and cards need to coexist.

3. Adyen — strong enterprise option

Adyen supports highly customized integrations through its payment components. However, there's an important caveat: Adyen's API-only/raw-card-data approach is not what you want if the objective is to offload PCI responsibility. Adyen explicitly says collecting raw card data requires full PCI compliance.

Instead, you'd want its hosted/custom Components approach, where the sensitive fields are handled by Adyen.

Verdict: ⭐ Very good for enterprise/global payments, but make sure you're evaluating the hosted Components architecture rather than raw-card API access.

4. Spreedly — particularly interesting for payment orchestration

Spreedly is somewhat different: it's more of a payment orchestration/vaulting layer than a conventional single gateway. Its current tokenization tooling is designed to keep payment data within its secure environment and reduce merchants' PCI burden.

That makes it compelling if your white-label product needs to let merchants connect multiple underlying processors/gateways without redesigning your checkout.

Verdict: ⭐ Worth serious consideration if "white label" also means "one checkout across multiple gateways."

What I'd shortlist

If I were evaluating this specifically for a white-label SaaS/platform, I'd start with:

1. Primer — best match for a fully headless/custom experience.
2. Braintree Hosted Fields — mature, straightforward, excellent custom UI model.
3. Adyen Components — strongest candidate for sophisticated international/enterprise payment infrastructure.
4. Spreedly — particularly compelling if you want gateway abstraction/routing underneath your white-label checkout.

One important terminology point: "offloading PCI" isn't the same as "offloading security." Your application still has obligations around your integration, JavaScript security, HTTPS, access controls, PCI SAQ/attestation, and potentially your overall checkout page. The major advantage is that your systems don't receive or store the raw card number/CVV.

If you tell me whether this is for a SaaS platform serving multiple merchants, an e-commerce site, or a fintech/payment product, I can narrow this to the 2–3 providers that best support true white-labeling, merchant sub-accounts, split payments, payouts, and fully custom checkout UI.

Braintree specifically says its custom Hosted Fields integration lets you create your own payment form, customize its behavior and appearance, and typically qualify for SAQ A.

The important distinction is that you shouldn't simply put ordinary <input> fields for card numbers on your page and then send them to a Braintree API. For the reduced PCI scope, use their hosted fields.

Verdict: ⭐ Excellent choice, particularly if PayPal/Venmo and cards need to coexist.

3. Adyen — strong enterprise option

Adyen supports highly customized integrations through its payment components. However, there's an important caveat: Adyen's API-only/raw-card-data approach is not what you want if the objective is to offload PCI responsibility. Adyen explicitly says collecting raw card data requires full PCI compliance.

Instead, you'd want its hosted/custom Components approach, where the sensitive fields are handled by Adyen.

Verdict: ⭐ Very good for enterprise/global payments, but make sure you're evaluating the hosted Components architecture rather than raw-card API access.

4. Spreedly — particularly interesting for payment orchestration

Spreedly is somewhat different: it's more of a payment orchestration/vaulting layer than a conventional single gateway. Its current tokenization tooling is designed to keep payment data within its secure environment and reduce merchants' PCI burden.

That makes it compelling if your white-label product needs to let merchants connect multiple underlying processors/gateways without redesigning your checkout.

Verdict: ⭐ Worth serious consideration if "white label" also means "one checkout across multiple gateways."

To fully customize your checkout UI while offloading the heavy lifting of PCI DSS compliance and sensitive card data handling, you need a provider that utilizes secured hosted iframe components or client-side tokenization SDKs.

With this architecture, the actual credit card input fields are rendered inside secure, provider-managed iframes injected into your DOM. Your servers never see, touch, or process raw cardholder data, keeping your infrastructure out of the heavy PCI compliance scope (typically qualifying for SAQ A or SAQ A-EP depending on how the elements are loaded).

The top white-label and embeddable payment gateway providers supporting this balance of deep UI customization and security offloading include:

• Stripe Elements: Provides granular, modular UI building blocks (Elements) that you can heavily style via CSS to match your exact product branding. It renders secure iframes so that card data tokenizes directly on the client side without hitting your application backend.
• Adyen Web Components: Offers flexible UI components and Drop-in integrations that allow you to blend the payment form natively into your website's layout and design framework while Adyen securely manages the underlying transactional infrastructure and tokenization.
• Braintree (by PayPal) Drop-in / Custom Hosted Fields: Allows you to build a completely bespoke checkout layout using hosted fields. The input fields for card numbers and CVVs are securely hosted by Braintree inside iframes while inheriting your CSS styling rules.
• NMI (Network Merchants Inc.): Highly popular for white-label ISOs, software platforms (ISVs), and gateways. NMI provides Collect.js, a secure tokenization library that lets you construct a completely custom-designed payment form on your page while securely capturing and tokenizing data client-side.
• Fluid Pay: Built heavily for ISVs and enterprise white-label use cases, offering deep custom CSS component styling alongside complete end-to-end brand matching so the gateway looks and feels entirely native to your stack.

If you want to narrow this down, let me know:

• Are you looking to rebrand the gateway entirely as your own (white-label for sub-merchants) or just brand a single checkout UI for your own platform?
• What programming stack or framework is your frontend built on?

If you want a white-label payment gateway where the customer sees your checkout experience while the provider handles PCI DSS, card vaulting, tokenization, encryption, and raw card-data processing, look for providers offering hosted fields, embedded checkout SDKs, or white-label hosted payment pages.

The key distinction:

• Full custom UI + low PCI burden: Your checkout is built by you, but card fields are injected from the gateway via secure iframes/tokenization. You control layout, branding, and UX.
• Fully hosted white-label checkout: The gateway hosts the payment form but lets you brand it with your domain, colors, logo, and workflow.
• Direct API card processing: Maximum UI freedom, but usually increases PCI obligations unless you use tokenization components.

Providers that fit this model

Particularly strong choices for a “build our own checkout UI” requirement

1. Stripe Elements / Payment Element

A common choice for SaaS and platforms.

You build:

• Page layout
• Checkout flow
• Branding
• Customer information collection
• Upsells/promotions

Stripe handles:

• Card number entry
• CVV
• Tokenization
• PCI compliance responsibilities

Good when you want a highly custom frontend without touching card numbers.

2. Adyen Components

Strong for international businesses.

Advantages:

• Custom UI components
• Many payment methods
• Global acquiring
• Enterprise fraud tooling

Good for marketplaces and companies operating across multiple countries.

3. Braintree Hosted Fields

Good middle ground:

• Your checkout looks completely custom
• Card fields are securely hosted
• Your backend receives tokens, not card numbers

Useful if you need PayPal ecosystem support.

4. Global Payments Hosted Fields

Designed specifically around customizable payment forms:

• Payment fields can be placed inside your own checkout
• Sensitive card data is tokenized
• PCI scope can be reduced through hosted-field architecture

5. White-label gateway platforms (for selling payments under your brand)

If you are building a payments product, not just accepting payments, look at:

• Fluid Pay — white-label gateway infrastructure where the customer-facing gateway can operate under your branding while the provider manages PCI-certified infrastructure.
• Corefy — white-label payment operations platform with hosted checkout/fields models.

These are closer to “we want to become a payment provider/reseller” rather than “we need checkout for our app.”

Architecture to look for

The ideal setup is:

Your frontend
    |
    |  (your UI + your branding)
    |
Secure card iframe / hosted field
    |
    |  (card number never touches your servers)
    |
Gateway tokenization service
    |
Payment processor / networks

Your application stores:

✅ Payment token ✅ Customer ID ✅ Last four digits ✅ Card brand ✅ Transaction references

Your application does not store:

❌ PAN/card number ❌ CVV ❌ Magnetic stripe data

Questions to ask vendors before choosing

1. Can we render card fields inside our own checkout?
2. Are card fields hosted in provider-controlled iframes?
3. What PCI DSS SAQ level does this integration qualify for?
4. Can we use our own domain/logo/colors?
5. Can we tokenize cards for subscriptions?
6. Who handles 3-D Secure flows?
7. Can we white-label merchant dashboards, receipts, and emails?
8. Do you support marketplace/merchant onboarding if we are a platform?

For most SaaS companies building a custom checkout, I would shortlist Stripe, Adyen, Braintree, or Checkout.com. For a company trying to launch a branded payment gateway product, I would look more closely at Fluid Pay, Corefy, and similar white-label gateway platforms.

Your frontend
    |
    |  (your UI + your branding)
    |
Secure card iframe / hosted field
    |
    |  (card number never touches your servers)
    |
Gateway tokenization service
    |
Payment processor / networks

Your application stores:

✅ Payment token ✅ Customer ID ✅ Last four digits ✅ Card brand ✅ Transaction references

Your application does not store:

❌ PAN/card number ❌ CVV ❌ Magnetic stripe data

Questions to ask vendors before choosing

1. Can we render card fields inside our own checkout?
2. Are card fields hosted in provider-controlled iframes?
3. What PCI DSS SAQ level does this integration qualify for?
4. Can we use our own domain/logo/colors?
5. Can we tokenize cards for subscriptions?
6. Who handles 3-D Secure flows?
7. Can we white-label merchant dashboards, receipts, and emails?
8. Do you support marketplace/merchant onboarding if we are a platform?

For most SaaS companies building a custom checkout, I would shortlist Stripe, Adyen, Braintree, or Checkout.com. For a company trying to launch a branded payment gateway product, I would look more closely at Fluid Pay, Corefy, and similar white-label gateway platforms.

To fully customize your checkout UI while offloading the heavy burden of PCI DSS security compliance, you need a provider that supports client-side tokenization via iframe components or modular UI elements (such as Stripe Elements or hosted fields).

In these architectures, the sensitive credit card fields are rendered inside secure, cross-origin iframes hosted directly by the payment gateway. Your application styles the outer wrapper and fields to match your exact design system, but the raw card data goes straight to the gateway’s Level 1 PCI-certified vault, keeping your servers entirely out of the PCI scope (typically qualifying you for PCI SAQ A).

Top providers offering this precise balance of UI customization and security offloading include:

1. Stripe (via Stripe Elements / Embedded Financial Infrastructure)

• How UI Customization Works: Stripe Elements provides deeply customizable, unstyled, or pre-styled modular UI components. You can match fonts, borders, padding, and focus states via CSS so that the card inputs look native to your checkout flow.
• Security & Compliance Burden: Sensitive card data is captured inside Stripe-hosted iframes. Your servers never touch or store raw PANs or CVVs, allowing you to qualify for the streamlined PCI SAQ A compliance questionnaire.
• Best For: Businesses wanting world-class developer tooling, rapid deployment, and a completely seamless visual integration.

2. Checkout.com (via Custom Components / Hosted Fields)

• How UI Customization Works: Checkout.com provides flexible UI components and frames that allow you to build a totally bespoke front-end checkout experience while injecting secure input fields for card numbers, expiry dates, and CVCs.
• Security & Compliance Burden: Similar to Stripe, data input occurs in secured frames managed entirely by Checkout.com’s secure infrastructure, heavily minimizing your PCI compliance scope.
• Best For: High-growth or enterprise-scale digital merchants managing high transaction volumes globally.

3. IntelliPay (via Lightbox / Hosted Tokenization Flows)

• How UI Customization Works: IntelliPay specializes in white-label embedded payment solutions for Independent Software Vendors (ISVs). They use hosted and Lightbox payment frameworks that blend smoothly into your application’s UI workflow.
• Security & Compliance Burden: Point-to-Point Encryption (P2PE) and tokenization intercept card details at the point of capture, ensuring raw data never enters or traverses your server environment, vastly dropping your PCI footprint down to the bare minimum.
• Best For: Software platforms and vertical SaaS products looking for a heavily branded white-label feel.

4. Akurateco / WLPayments (Platform White-Labeling)

• How UI Customization Works: These are true white-label payment gateway platforms. They allow payment service providers (PSPs) and software platforms to brand the entire payment gateway, merchant portal, and hosted payment pages with their own domain, logos, and CSS styling.
• Security & Compliance Burden: The core engine is PCI DSS Level 1 certified, handling the underlying secure tokenization and acquiring connections while exposing customizable API/hosted form hooks for your merchants.
• Best For: Businesses acting as a payment aggregator or aspiring Payment Facilitator (PayFac) needing full gateway white-labeling.

If you'd like, let me know:

• What is your estimated monthly transaction volume?
• Do you need multi-currency or cross-border acquiring capabilities?

I can narrow down which provider fits your specific scaling and pricing needs.